Mocking actors for making music seems somewhat churlish, not least because so many singers move into movies with only an occasional grumble from the public. In the case of the British-born, LA-based Oscar nominee Minnie Driver there is little doubt that a love of singing, rather than a quest for more fame, is her main motivation. Before her acting career took off, Driver fronted a band signed to a major label and, despite scant commercial success for her solo debut, Everything I've Got in My Pocket (2004), this week she released a follow-up, the country-flavoured Seastories.

Still, that a hastily arranged one-off show in Soho was practically full undoubtedly had as much to do with her former film roles as her music. In a short, dark, off-one-shoulder dress, with her wavy hair pinned back, Driver was a source of fascination for fans as soon as she stepped barefoot onstage. Heavily pregnant, her belly protruded from her dress so far that she claimed she couldn't play guitar. And, after the flashing of camera phones, she asked the seated crowd to stop so sweetly - “Enough of the cameras already,” she joked. “You know, I am famous” - that almost everyone obliged.

When she sang, Driver was surprisingly sweet too. Backed by a guitarist, bassist and double bass player, she recalled Fiona Apple on the Seastories track Stars & Satellites, while the country ballad Beloved was delivered with a deep, breathy, beguiling vocal a mile away from the public school speaking voice in which she informed the audience that she desperately needed to pee.

Seastories apparently deals with a failed affair, but if its love-heavy lyrics lacked flair. A more heartfelt subject for her next set of songs might be family. Driver frequently referred to her unborn baby - Fast As You Can made its heartbeat race, she said - dedicated the country-rocker Mockingbird to her mum and London Skies to her dad and played the encore for her sister Kate and “anyone knocked up”.

By then she had just about pulled off a reggae-tinged cover of Stevie Wonder's Masterblaster and done a decent reworking of the Kinks' Waterloo Sunset. Some actors, it seems, aren't bad singers either.

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